Impact of annealing environment on electrical properties of yttrium-doped hafnium zirconium dioxide thin films prepared by the solution process

Ferroelectric yttrium-doped hafnium zirconium dioxide (Y-HZO) was fabricated on Pt/Ti/SiO2/Si substrate by the solution process under various annealing environments. A metal-ferroelectric-metal structure with Pt as the top electrode was fabricated and characterized. Samples annealed at 600-800 degrees C in a vacuum environment showed ferroelectricity, which was confirmed by the polarization-electric field and capacitance-voltage measurements. The ferroelectric properties were dramatically improved when samples were annealed in a vacuum at 800 degrees C due to the decrease in leakage current compared to the Y-HZO films annealed at 800 degrees C in oxygen and nitrogen.